From: Derrick Stolee <derrickstolee@xxxxxxxxxx>
This patch extracts the common code used to compute topological levels
and corrected committer dates into a common routine,
compute_reachable_generation_numbers(). For ease of reading, it only
modifies compute_topological_levels() to use this new routine, leaving
compute_generation_numbers() to be modified in the next change.
This new routine dispatches to call the necessary functions to get and
set the generation number for a given commit through a vtable (the
compute_generation_info struct).
Computing the generation number itself is done in
compute_generation_from_max(), which dispatches its implementation based
on the generation version requested, or issuing a BUG() for unrecognized
generation versions. This does not use a vtable because the logic
depends only on the generation number version, not where the data is
being loaded from or being stored to. This is a subtle point that will
make more sense in a future change that modifies the in-memory
generation values instead of just preparing values for writing to a
commit-graph file.
This change looks like it adds a lot of new code. However, two upcoming
changes will be quite small due to the work being done in this change.
Co-authored-by: Taylor Blau <me@xxxxxxxxxxxx>
Signed-off-by: Taylor Blau <me@xxxxxxxxxxxx>
Signed-off-by: Derrick Stolee <derrickstolee@xxxxxxxxxx>
---
commit-graph.c | 106 ++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 83 insertions(+), 23 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c
index c11b59f28b3..4356c8c1f4b 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -1446,24 +1446,52 @@ static void close_reachable(struct write_commit_graph_context *ctx)
stop_progress(&ctx->progress);
}
-static void compute_topological_levels(struct write_commit_graph_context *ctx)
+struct compute_generation_info {
+ struct repository *r;
+ struct packed_commit_list *commits;
+ struct progress *progress;
+ int progress_cnt;
+
+ timestamp_t (*get_generation)(struct commit *c, void *data);
+ void (*set_generation)(struct commit *c, timestamp_t gen, void *data);
+ void *data;
+};
+
+static timestamp_t compute_generation_from_max(struct commit *c,
+ timestamp_t max_gen,
+ int generation_version)
+{
+ switch (generation_version) {
+ case 1: /* topological levels */
+ if (max_gen > GENERATION_NUMBER_V1_MAX - 1)
+ max_gen = GENERATION_NUMBER_V1_MAX - 1;
+ return max_gen + 1;
+
+ case 2: /* corrected commit date */
+ if (c->date && c->date > max_gen)
+ max_gen = c->date - 1;
+ return max_gen + 1;
+
+ default:
+ BUG("attempting unimplemented version");
+ }
+}
+
+static void compute_reachable_generation_numbers(
+ struct compute_generation_info *info,
+ int generation_version)
{
int i;
struct commit_list *list = NULL;
- if (ctx->report_progress)
- ctx->progress = start_delayed_progress(
- _("Computing commit graph topological levels"),
- ctx->commits.nr);
- for (i = 0; i < ctx->commits.nr; i++) {
- struct commit *c = ctx->commits.list[i];
- uint32_t level;
-
- repo_parse_commit(ctx->r, c);
- level = *topo_level_slab_at(ctx->topo_levels, c);
+ for (i = 0; i < info->commits->nr; i++) {
+ struct commit *c = info->commits->list[i];
+ timestamp_t gen;
+ repo_parse_commit(info->r, c);
+ gen = info->get_generation(c, info->data);
+ display_progress(info->progress, info->progress_cnt + 1);
- display_progress(ctx->progress, i + 1);
- if (level != GENERATION_NUMBER_ZERO)
+ if (gen != GENERATION_NUMBER_ZERO && gen != GENERATION_NUMBER_INFINITY)
continue;
commit_list_insert(c, &list);
@@ -1471,31 +1499,63 @@ static void compute_topological_levels(struct write_commit_graph_context *ctx)
struct commit *current = list->item;
struct commit_list *parent;
int all_parents_computed = 1;
- uint32_t max_level = 0;
+ uint32_t max_gen = 0;
for (parent = current->parents; parent; parent = parent->next) {
- repo_parse_commit(ctx->r, parent->item);
- level = *topo_level_slab_at(ctx->topo_levels, parent->item);
+ repo_parse_commit(info->r, parent->item);
+ gen = info->get_generation(parent->item, info->data);
- if (level == GENERATION_NUMBER_ZERO) {
+ if (gen == GENERATION_NUMBER_ZERO) {
all_parents_computed = 0;
commit_list_insert(parent->item, &list);
break;
}
- if (level > max_level)
- max_level = level;
+ if (gen > max_gen)
+ max_gen = gen;
}
if (all_parents_computed) {
pop_commit(&list);
-
- if (max_level > GENERATION_NUMBER_V1_MAX - 1)
- max_level = GENERATION_NUMBER_V1_MAX - 1;
- *topo_level_slab_at(ctx->topo_levels, current) = max_level + 1;
+ gen = compute_generation_from_max(
+ current, max_gen,
+ generation_version);
+ info->set_generation(current, gen, info->data);
}
}
}
+}
+
+static timestamp_t get_topo_level(struct commit *c, void *data)
+{
+ struct write_commit_graph_context *ctx = data;
+ return *topo_level_slab_at(ctx->topo_levels, c);
+}
+
+static void set_topo_level(struct commit *c, timestamp_t t, void *data)
+{
+ struct write_commit_graph_context *ctx = data;
+ *topo_level_slab_at(ctx->topo_levels, c) = (uint32_t)t;
+}
+
+static void compute_topological_levels(struct write_commit_graph_context *ctx)
+{
+ struct compute_generation_info info = {
+ .r = ctx->r,
+ .commits = &ctx->commits,
+ .get_generation = get_topo_level,
+ .set_generation = set_topo_level,
+ .data = ctx,
+ };
+
+ if (ctx->report_progress)
+ info.progress = ctx->progress
+ = start_delayed_progress(
+ _("Computing commit graph topological levels"),
+ ctx->commits.nr);
+
+ compute_reachable_generation_numbers(&info, 1);
+
stop_progress(&ctx->progress);
}
--
gitgitgadget
